Congenital self-healing non-Langerhans cell histiocytosis.

Clinical, morphological, ultrastructural and immunological studies were performed in a case of congenital self-healing non-Langerhans cell histiocytosis. The patient showed several aspects that have not been published before: a large nodule in the vulvar region, vesiculobullous elements and pneumonia (asymptomatic). The relationship of the vesicles and pneumonia to the histiocytic disorder is not clear. Ultrastructurally, worm-like (comma-shaped) particles, dense bodies and Birbeck granules were not found. Histiocytes were Leu-6 negative, and S100 (partly), Leu M3 and HLA-DR positive. Positive reactions were also obtained with anti-lysozyme and non-specific esterase. Several aspects of this case and of others described previously are discussed.